PRELIMINARY REPORT ON EXPEDITION EASTROPIC 



By 

 Joseph E. King, Thomas S. Austin, and Maxwell S. Doty 



The EASTROPIC Expedition was a 

 cooperative oceanographic survey of the central 



The California Department of Fiah and Game 



9hing 



An Announcement (which read as fellows) was recently issued by the 

 Bureau of Commercial Fisheries Biological Laboratory Honolulu, concern- 

 ing an error Ir, depths of reversal computed from the readings of unpro- 

 tected and protected reversing thermometers 



"Recently, it was discovered that the depths of reversal of 

 the Nansen bottles as calculated at the Honolulu Biological Laboratory 

 from temperature differences of anj^irote.cted ar^d protected reversing 

 thermometers; are In error These depths, which are in excess of the 

 correct depth, may be reduced tc the proper value by the use of a cor- 

 rection factor, as described below. 



At the time the data processing system in use at this laboratory 

 was being established, a table of the factor 1/ (.Q^Pm) was prepared for 

 use in computing the depths of reversal from the readings of unprotected 

 thermometers; Q represento the pressure-constant of an unprotected ther- 

 mometer, and ptji represer.ts the mean density of the water column above 

 the depth of thermometer reversal, which was taken to be 1.0303 in all 

 cases. An error occurred in the calculation such that, instead of 

 l/(Qxptn). the table consisted of values of (1/Q)mPjj,. This error is 

 present in all of the depth data which have been published by this labo- 

 ratory under its previous name ^ Pacific Oceanic Fishery Investigations, 

 and under its present rame Honolulu Biological Laboratory up to and 

 including 1960. Therefore, ii; making use of the data published by this 

 laboratory before 1961 all depths should be corrected by dividing each 

 by (Pm) i which is equal to 1.061^. MultipHcation of all the published 

 depths by 0.9C2 will give the proper value for the depth of each observa- 

 tion." 



DPIC, 



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ining 



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 nake 

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Subsequent analyses have sVov^^ tr.ai. the error described above is present 

 only in the data from those cruises made by vessels of the Bureau of 

 Commercial Fisheries Biological Laboiatory, Honolulu, after Hugh M, Smith 

 cruise 20 (Febr aary-Aprll 19"j}) Cruises for which data containing this 

 error have beer, published are listed below with the appropriate publica- 

 tion references. 



DEC I "^.^ NOV 23 

 MARQUESAS t 



Figure 1. --Track of the Hugh M. Smith (cruise 31) on the EASTROPIC 

 Expedition, September 23 to December 17, 1955. 



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